Responsive Web Design Projects - Build a Product Landing Page

Tell us what’s happening:
Describe your issue in detail here.

Your code so far

<!-- file: index.html -->
    <header id="header">
      <img src="https://cdn.freecodecamp.org/testable-projects-fcc/images/product-landing-page-logo.png" alt="" id="header-img">
      <nav id="nav-bar">
        <a href="#header-img" class="nav-link">Features</a>
        <a href="#header" class="nav-link">How It Works</a>
        <a href="#nav-bar" class="nav-link">Pricing</a>
      </nav>
    </header>
    <video src="https://youtu.be/y8Yv4pnO7qc" id="video"></video>
    <form action="https://www.freecodecamp.com/email-submit" id="form">
      <input type="email" id="email" placeholder="Nhập email" name="email">
      <input type="submit" id="submit">
    </form>
<link rel="stylesheet" href="styles.css">
<meta name="viewport" content="width=device-width, initial-scale=1">
/* file: styles.css */
#header{
    display: flex;
     height: 50px;
justify-content: space-between;
border:1px solid black;
}
@media screen and (max-width:900px) {
        #header{
   display: flex;
     }
}
#header img {
    width: 40%;  
}

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.0.0 Safari/537.36

Challenge: Responsive Web Design Projects - Build a Product Landing Page

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